Client device and server device for the secured activation of functions of a client

Abstract

A client device for the secured activation of functions of a client, a server device for providing a password for the client device, and corresponding methods. The client device has a storage unit for storing a plurality of service keys, each service key defining at least one function of the client and being allocated to a password, a receiving unit for receiving a password from a server, and a processing unit for comparing the plurality of service keys with the received password, for selecting the service key to which the received password is allocated, and for activating at least one function of the client which is contained in the selected service key.

The invention claimed is: 
     
       1. A client device for the secured activation of functions of a client, comprising:
 a hardware storage for storing a plurality of service keys, wherein each service key is stored in the hardware storage during production of the client device, wherein each service key defines at least one function of the client, wherein each service key includes authorization data, and wherein each service key is allocated to a password, wherein the password is formed deterministically with a key derivation function from the authorization data, 
 a receiver for receiving said password from a server, and 
 a processor for comparing the plurality of service keys with the received password, for selecting the service key to which the received password is allocated, and for activating the at least one function of the client. 
 
     
     
       2. The client device as claimed in  claim 1 , wherein the password consists of a sequence of less than 20 characters. 
     
     
       3. The client device as claimed in  claim 1 , wherein each service key is signed with a private key of the server. 
     
     
       4. The client device as claimed in  claim 3 , wherein the processor is configured to verify the signature of the selected service key by means of a stored public key of the server. 
     
     
       5. The client device as claimed in  claim 1 , wherein the service key defines a period of an activation of the at least one function of the client. 
     
     
       6. The client device as claimed in  claim 5 , wherein the processor is configured to deactivate the selected service key after expiry of the period of activation. 
     
     
       7. The client device as claimed in  claim 1 , wherein a transmitter for transmitting a service key request to the server, the service key request specifying at least one function of the client for activation. 
     
     
       8. The client device as claimed in  claim 7 , wherein the service key request specifies at least one of a period of activation and an identifier of the client. 
     
     
       9. The client device as claimed in  claim 7 , wherein each stored service key contains at least one of a period of activation and an identifier of the client. 
     
     
       10. The client device as claimed in  claim 9 , wherein the processor is configured to check the selected service key with respect to the at least one of the period of activation and the identifier of the client which are specified in the service key request. 
     
     
       11. A server device for providing a password for a client device as claimed in  claim 1 , comprising:
 a hardware storage for storing a plurality of service keys, each service key defining at least one function of the client and being allocated to the password, 
 a receiver for receiving a service key request, the service key request specifying at least one function of the client for activation, 
 a processor for selecting a service key from the plurality of service keys based on the received service key request, and 
 a transmitter for transmitting the password which is allocated to the selected service key, to the client. 
 
     
     
       12. A system comprising: a client which has a client device and a server which has a server device as claimed in  claim 11 , the client and the server being configured to communicate with one another. 
     
     
       13. The client device of  claim 1 , wherein activation of the at least one function of the client activated by the service key is required for service and maintenance of the client. 
     
     
       14. A method for the secured activation of functions of a client, comprising:
 storing a plurality of service keys at a client device of the client, wherein each service key is stored at the client device of the client during production of the client device, wherein each service key defines at least one function of the client, wherein each service key includes authorization data, and wherein each service key is allocated to a password, 
 generating said password deterministically with a key derivation function from the authorization data, 
 receiving the password from a server, 
 comparing the stored plurality of service keys with the received password, 
 selecting the service key to which the received password is allocated, and 
 activating the at least one function of the client which is contained in the selected service key. 
 
     
     
       15. A computer program product comprising, wherein the hardware storage having computer readable program code stored therein, said program code executable by a processor of a computer system to implement the method as claimed in  claim 14  to be performed on a program-controlled computer. 
     
     
       16. The method of  claim 14 , wherein activation of the at least one function of the client activated by the service key is required for service and maintenance of the client. 
     
     
       17. A method for providing a password for a client device, comprising
 storing a plurality of service keys at a client device of the client, wherein each service key includes authorization data and wherein each service key is allocated to a password, 
 generating said password deterministically with a key derivation function from the authorization data, 
 receiving a service key request, the service key request specifying at least one function of the client for activation, 
 selecting a service key from the plurality of stored service keys based on the received service key request, and 
 transmitting the password which is allocated to the selected service key to the client.